In the packaging of fresh seafood, if the packaging material does not have a relatively high oxygen transmission rate (“OTR”), under certain conditions the result can be the growth of clostridiyum botulinum, which can produce illness for a consumer of the seafood. Recently the United States Food and Drug Administration set a new standard for the packaging of seafood because of the risk of growth of clostridiyum botulinum. Under the new standard, the packaging film must have an oxygen (i.e., O2) transmission rate of at least 10,000 cc/m2/24 hr at @STP (i.e., at standard temperature, pressure, and relative humidity, which are 73° F., 0% relative humidity, and atmospheric pressure at sea level).
Previously, packaging films having oxygen transmission rates of from 2,000 to 5,000 cc/m2/24 hr at @STP have been used for the packaging of seafood. However, with the new 10,000 cc/m2/24 hr at @STP requirement, these films have too low an oxygen transmission rate to meet the new FDA oxygen transmission rate for packaging seafood.
Films exhibiting a relatively high oxygen transmission rate have for some time been used for the packaging of various food products such as fresh produce, fruit, and cheese. Gas transmission rates for the packaging of these foods have traditionally been tailored to a desired level by making a relatively thin film (thickness generally in the range of from about 1 mil to about 1¼ mil) which contains at least one polymer having a relatively high oxygen transmission rate. In general, produce need not be packaged in a film having high abuse-resistance. Thus, the 1 mil to 1¼ mil produce high OTR film have provided good performance for the packaging of produce.
The packaging of seafood in a film having the desired oxygen transmission rate is rendered problematic by the opposing requirements of a film having both a high OTR and high abuse-resistance. Seafood packaging films require a more abuse-resistant film than produce does. Thickening the 1 mil to 1¼ mil produce films to provide the desired abuse-resistance results in a film having an OTR too low to be suitable for the packaging of seafood.
It would be desirable to provide a film exhibiting a combination of higher abuse-resistance than produce films while at the same time providing the film with a relatively high oxygen transmission for the packaging of fresh seafood. If such a film is available, fresh seafood which is packaged in the film could be quickly chilled by being placed in a low-temperature brine solution, resulting in a product with longer shelf life and higher quality when reaching the consumer.